Understanding inference as a source of knowledge: children's ability to evaluate the certainty of deduction, perception, and guessing.

Three experiments investigated children's understanding of inference as a source of knowledge. Children observed a puppet make a statement about the color of one of two hidden toys after the puppet (a) looked directly at the toy (looking), (b) looked at the other toy (inference), or (c) looked at neither toy (guessing). Most 4-, 5-, and 6-year-olds did not rate the puppet as being more certain of the toy's color after the puppet looked directly at it or inferred its color than they did after the puppet guessed its color. Most 8 and 9-year-olds distinguished inference and looking from guessing. The tendency to explain the puppet's knowledge by referring to inference increased with age. Children who referred to inference in their explanations were more likely to judge deductive inference as more certain than guessing.

Children's understanding of inferential knowledge.

The understanding of inference as a source of knowledge for 4- and 6-year-old children was investigated. Children and a puppet were shown 2 toys of different colors. The toys were hidden in separate plastic cans. After the puppet looked into 1 of the cans, 6-year-olds, but not 4-year-olds, usually judged that the puppet knew the color of the toy in the other can as well. The finding that 6-year-olds attributed inferential knowledge to another observer is interpreted as evidence that children begin to understand the role of cognitive processes in knowledge acquisition around the age of 6 years.

Epistemological development in adolescence and adulthood: a multidimensional framework.

Theories of epistemological development are reviewed. A framework describing variations in adolescents' and adults' intuitive conceptions of knowledge is proposed. Within the proposed framework, naive epistemologies are conceptualized in terms of their assumptions concerning (a) the nature of the knowledge acquisition process, (b) the degree of correspondence between knowledge and reality, (c) the certainty of knowledge, (d) the commensurability of knowledge across individuals, (e) the degree to which knowledge forms or inheres in a coherent system of thought, (f) the nature of meaning, (g) the appropriate procedures for evaluating competing beliefs, (h) the nature and role of authorities as sources of knowledge and justification, and (i) the nature of reality. This framework is used to describe possible developmental changes in adolescents' and adults' concepts of knowledge and to suggest how future researchers might address core issues concerning epistemological development.

Preschool children's use of information about age and perceptual access to infer another person's knowledge.

Preschool children's use of information about age and perceptual experience to infer other people's knowledge was investigated. Because young children may view adults as omniscient, the hypothesis that 3-year-olds regard an observer's age and perceptual experience as equally important when inferring the observer's knowledge was tested. In Experiment 1, 3- and 4-year-olds were asked to judge which of 2 observers, 1 adult and 1 same-age child, knew the identity of a hidden object. On some trials, the adult looked at the hidden object; on other trials, the same-age peer looked at the hidden object. The children who were 3.5 years old relied on information about perceptual experience when judging knowledge. However, the younger 3-year-olds often chose the peer, even though the adult was knowledgeable. The children may have chosen the peer on the basis of familiarity; therefore, adult and child dolls were used in Experiment 2. Neither the 3-year-olds nor the 4-year-olds attributed knowledge on the basis of age rather than perceptual experience.

There's more to the picture than meets the eye: young children's difficulty understanding biased interpretation.

5 experiments investigated children's understanding that expectations based on prior experience may influence a person's interpretation of ambiguous visual information. In Experiment 1, 4- and 5-year-olds were asked to infer a puppet's interpretation of a small, ambiguous portion of a line drawing after the puppet had been led to have an erroneous expectation about the drawing's identity. Children of both ages failed to ascribe to the puppet an interpretation consistent with the puppet's expectation. Instead, children attributed complete knowledge of the drawing to the puppet. In Experiment 2, the task was modified to reduce memory demands, but 4- and 5-year-olds continued to overlook the puppet's prior expectations when asked to infer the puppet's interpretation of an ambiguous scene. 6-year-olds responded correctly. In Experiment 3, 4- and 5-year-olds correctly reported that an observer who saw a restricted view would not know what was in the drawing, but children did not realize that the observer's interpretation might be mistaken. Experiments 4 and 5 explored the possibility that children's errors reflect difficulty inhibiting their own knowledge when responding. The results are taken as evidence that understanding of interpretation begins at approximately age 6 years.

Children's understanding of action lines and the static representation of speed of locomotion.

Children's understanding of the static representation of speed of locomotion was explored in 2 experiments. In Experiment 1, 20 7-year-olds and 20 9-year-olds drew pictures of 2 people walking and running at different speeds. Children then made judgments about pairs of unambiguous drawings of a person walking or running, as did a sample of 20 adults. The drawings varied according to whether action lines, background lines, or no lines were present. Children were asked to say which figure appeared to be moving faster. In Experiment 2, 20 7-year-olds, 20 9-year-olds, and 21 adults sorted ambiguous drawings of a person walking and running at different speeds. The pictures again contained action lines, background lines, or no lines. In the drawing task, children more frequently used page position and biomechanical information than action lines to represent fast and slow walking and running. In the judgment task, 7- and 9-year-olds offered equivalent judgments of action lines and background lines, whereas adults distinguished between these pictorial devices. In the sorting task, all subjects distinguished between action lines and background lines and judged that pictures containing action lines looked faster than pictures containing background lines and pictures without lines. Taken together, the results indicate that subjects' judgments were influenced by the form of locomotion and degree of ambiguity in the depicted events they saw. The findings are consistent with the view that different categories of pictorial devices exist, but the effectiveness of each device is contingent upon the perceiver's experience with it and the context in which it appears.

Early understanding of perception as a source of knowledge.

Two studies investigated preschool children's ability to infer another person's knowledge or ignorance on the basis of that person's recent perceptual experience. In Experiment 1 children were questioned about their own and a puppet's knowledge of a hidden object's color and about their own and the puppet's ability to see the hidden object. Three- and 4-year-olds attributed knowledge and perceptual experience to the person (either themselves or the puppet) who had viewed the hidden object, but not to the person who did not view it. Experiment 2 further investigated 3-year-olds understanding of perception as a source of knowledge. Children were asked to indicate which of two puppets, one who had viewed a hidden object and one who had not, would be able to tell them the object's color. Children chose the correct puppet more often than would be predicted by chance. The results of these experiments suggest that understanding of perception as a source of knowledge is present by the age of 3 years.

Young children's knowledge about visual perception: projective size and shape.

Although recent research indicates that an increased sensitivity to visual appearances develops around 4 or 5 years of age, evidence from perceptual studies suggests that certain types of appearances, that is, projective size and shape, are not noticed or understood until at least 7. 4 experiments investigated preschool children's knowledge of the projective size--distance and projective shape--orientation relationships. In Experiment 1, 3- and 4-year-olds were asked whether an object should be moved farther or nearer in order to increase or decrease its apparent size. 4-year-olds performed significantly better than chance, but 3-year-olds did not. Experiment 2 showed that 3-year-olds are able to perceive projective size changes, indicating that although they do not fully understand the projective size-distance relationship, the necessary perceptual information is potentially available to them. In Experiment 3, 3- and 4-year-olds were asked to indicate how a circular object should be rotated to make it appear either circular or elliptical. Again, 4-year-olds performed significantly better than chance, but 3-year-olds did not. Again also, the results of Experiment 4 indicate that although 3-year-olds are not aware of the projective shape-orientation relationship, they are capable of attending to changes in projective shape. Thus, the constraints on children's knowledge of the projective size-distance and projective shape-orientation relationships seem to be at least partly cognitive rather than wholly perceptual. These results are interpreted as further evidence for the acquisition of level 2 percept knowledge during early childhood.

Intellectual realism: the role of children's interpretations of pictures and perceptual verbs.

Intellectual realism refers to the tendency of young children to indicate incorrectly all that is present in an object array when asked to indicate only what they can see of it from a particular perspective. 3 experiments tested and confirmed the hypotheses that children's interpretation of (a) pictorial conventions and of (b) the expression "look like" may increase this tendency. The results of this and other studies suggest that young children's difficulties with adult pictorial conventions, with the wording of task instructions, and with the concept of a momentary, view-determined appearance can all lead to intellectual realism errors.